When an ignition key is set to the LOCK position and is removed from a key cylinder on a steering device having a steering lock apparatus, a lock pint protrudes toward the axial center of a steering shaft. As a result, the tip of the lock pin fits into a keylock hole in a keylock collar pressed around the steering shaft. The steering shaft is fixed to a column and is prevented from being rotated.
A conventional steering device having the steering lock apparatus configures a housing for containing the steering lock apparatus independently of the column. The housing is bolted on the column that rotatably supports the steering shaft.
A thief may steal a vehicle by loosening and removing the bolt from the steering lock apparatus on such conventional steering device. To prevent a thief from loosening the bolt, the bolt is so structured that fastening the bolt at a specified torque wrenches off a tool-engaging section at a bolt head section.
When the column is made of an aluminum alloy, however, the column intensity is small. A thief may use a special tool to break a flange where the bolt is fastened or to apply shock to the bolt head section, rotate and loose the bolt, and remove the steering lock apparatus from the column, and the vehicle may be stolen.
The steering devices described in non-patent documents 1 and 2 increase rigidity for attaching the steering lock apparatus housing to the column. The steering device described in the non-patent document 1 increases rigidity for attaching the steering lock apparatus housing to the column by welding a flange made of a thick steel plate to a steel-pipe column. The steering device described in the non-patent document 2 increases rigidity for attaching the steering lock apparatus housing to the column by attaching an aluminum die-cast housing to a steel-pipe column via a reinforcing plate made of a steel plate. The steering device described in the non-patent document 3 includes an aluminum die-cast housing attached to a flange made of a steel plate using an antitheft bolt.
The steering devices described in non-patent documents 1 and 2 relate to the steel-pipe column and do not include any countermeasure against destruction of an aluminum-alloy column near the flange to be bolted. The steering devices described in non-patent documents 1, 2, and 3 use the exposed bolt head section. A special tool may be used to apply shock to the bolt head section and rotate and loosen the bolt. The column may be removed from the steering lock apparatus and the vehicle may be stolen.